This paper describes the development of a derivatization procedure — silylation using BSTFA (N,O-bis(trimethylsilyl)-trifluoroacetamide) — for the simultaneous GC-MS analysis of a wide range of water-soluble organics in atmospheric aerosols. The reaction operating conditions were optimized in order to achieve the highest response for a large number of dicarboxylic acids and sugars. Optimization was carried out using the response surface methodology (RSM) including central composite design (CCD). The factors considered were: (i) reaction temperature (50°C-90°C), (ii) the reaction duration (60 min-90 min), (iii) reagent concentrations (10%-100% of the total solution volume) and (iv) pyridine concentration (0%-50% of the derivatization reagent). In addition, the optimum derivatization conditions were determined by considering the experimental limitations of the operative constrains and verified on real samples extracted from PM filters. The optimized procedure was extended to a broader range of 25 target analytes that are relevant chemical markers, i.e., 18 carboxylic acids and 7 sugars. In addition, the applicability of the optimized procedure was verified in environmental matrices from PM filters collected under different conditions, i.e. different seasons (summer vs. winter), different sampling sites (urban vs. rural), different particle size dimensions (PM2.5 vs. PM1).
OPTIMIZATION OF THE SILYL-DERIVATION PROCEDURE FOR SIMULTANEOUS DETERMINATION OF CARBOXYLIC ACIDS AND SUGARS IN PM SAMPLES
BACCO, Dimitri;PIETROGRANDE, Maria Chiara;PASTI, Luisa
2010
Abstract
This paper describes the development of a derivatization procedure — silylation using BSTFA (N,O-bis(trimethylsilyl)-trifluoroacetamide) — for the simultaneous GC-MS analysis of a wide range of water-soluble organics in atmospheric aerosols. The reaction operating conditions were optimized in order to achieve the highest response for a large number of dicarboxylic acids and sugars. Optimization was carried out using the response surface methodology (RSM) including central composite design (CCD). The factors considered were: (i) reaction temperature (50°C-90°C), (ii) the reaction duration (60 min-90 min), (iii) reagent concentrations (10%-100% of the total solution volume) and (iv) pyridine concentration (0%-50% of the derivatization reagent). In addition, the optimum derivatization conditions were determined by considering the experimental limitations of the operative constrains and verified on real samples extracted from PM filters. The optimized procedure was extended to a broader range of 25 target analytes that are relevant chemical markers, i.e., 18 carboxylic acids and 7 sugars. In addition, the applicability of the optimized procedure was verified in environmental matrices from PM filters collected under different conditions, i.e. different seasons (summer vs. winter), different sampling sites (urban vs. rural), different particle size dimensions (PM2.5 vs. PM1).I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
